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Biomedical subjects

M J Gil

Publications and source records attributed to M J Gil.

At least 37 records · Page 2Linked to original sources
PubMed1996

Value of PSA (prostate-specific antigen) in the detection of prostate cancer in patients with urological symptoms. Results of a multicentre study.

The aim of this multicentre study was to assess the usefulness of prostate-specific antigen (PSA) as a diagnostic procedure for prostate cancer in patients with urological symptoms, and compare it with digital rectal examination (DRE). The study included 2054 urological patients, aged over 50 years, and PSA levels were measured using an automated enzyme immunoassay. In the 680 cases with PSA levels > 3 micrograms/l and/or suspect DRE, transrectal ultrasound and prostate biopsy were also performed, leading to a diagnosis of cancer in 131 cases. The sensitivity of PSA was higher (95% and 73% for the cut-off values of 3 and 10 micrograms/l, respectively) than DRE (69%), both parameters being complementary. When DRE and PSA (> 10 micrograms/l) were combined, 118 cancers were diagnosed, with a PPV of 37%. We recommend using PSA and DRE in combination as a diagnostic procedure for prostate cancer in urological patients, since both methods are complementary.

Age Distribution↗
PubMed1996

Cholinergic modulation of spontaneous hypothalamic-pituitary-adrenal activity and its circadian variation in man.

Controversy still exists regarding the role of cholinergic pathways in the regulation of the hypothalamic-pituitary-adrenal axis in man. We studied the effects of the administration of placebo, pyridostigmine (PD); 120 mg, orally), and the combination of PD and pirenzepine (PZP; 100 mg, orally) on ACTH, cortisol, and GH secretion at 0730 and 2230 h in seven normal males. PD induced a clear decrease in ACTH levels at both times of the day compared to treatment with placebo, producing higher suppression in the nocturnal period (34.4 +/- 5.8% vs. 21.8 +/- 10.7%). The combination PD and PZP prevented the inhibitory action of PD on ACTH secretion in the morning, but not in the evening, when ACTH values showed a decrease similar to that seen after giving PD alone (38.1 +/- 5.6% vs. 34.4 +/- 5.8%, respectively). Cortisol values declined only when the association PD plus PZP was given in the evening. GH levels had a significant increase after PD administration in the morning (4.1 +/- 1.2 ng/mL) and in the evening (10.2 +/- 1.6 ng/mL), confirming that cholinergic stimulation was taking place, whereas the addition of PZP to PD induced a significant attenuation of these responses. It is concluded that cholinergic pathways have a inhibitory role in ACTH secretion in man. M1 muscarinic receptors seem to be involved in the diurnal inhibition of PD, whereas our observations are consistent with the mediation of another type of cholinergic receptors as an explanation for the nocturnal effect of PD on ACTH secretion. PD did not alter the circadian variation in the hypothalamic-pituitary-adrenal axis, whereas the association of PD and PZP increased the differences between diurnal and nocturnal ACTH values, suggesting a modulatory effect of the cholinergic system on the circadian rhythm of ACTH secretion.

Adrenocorticotropic Hormone↗
PubMed1996

[Growth factors and mitogenic activity in experimental hypercholesterolemia].

INTRODUCTION: Hypercholesterolemia is associated with increased platelet reactivity and changes in megakaryopoiesis, which might influence the synthesis of growth factors in the megakaryocyte. MATERIAL AND METHODS: 20 miniature pigs were randomly assigned to received 18 weeks of either regular pig chow feed (control group, n = 10) or a high cholesterol diet (cholesterol group, n = 10). Platelet count, mean platelet volume, platelet distribution width and bleeding time were determined in both groups. Intraplatelet and serum mitogenic activity was quantified by Swiss 3T3 and vascular smooth muscle cells proliferation assays. Insulin-like growth factor I and platelet-derived growth factor (BB isoform) levels were quantified in platelet lysates and in serum in both groups. RESULTS: Hypercholesterolemia was associated to a significant decrease in mean platelet volume and bleeding time, but it did not affect the proliferative effect of serum and platelet lysates nor its growth factor content. CONCLUSIONS: Taken together, our results suggest that although hypercholesterolemia affects platelet reactivity, its atherosclerosis-promoting effects cannot be explained by a direct effect on vascular smooth muscle cell proliferation or by changes in serum or intraplatelet growth factor content.

3T3 Cells↗
PubMed1995

Toward the biochemical assessment of myocardial fibrosis in hypertensive patients.

The serum concentrations of amino-terminal procollagen type III and carboxy-terminal procollagen type I-derived peptides, which have been proposed as useful markers of the tissue synthesis of collagen types III and type I, respectively, were abnormally increased in patients with essential hypertension and became normal after angiotensin-converting enzyme (ACE) inhibition. An association was found between baseline serum concentrations of these peptides and left ventricular hypertrophy, diastolic dysfunction, and ventricular arrhythmias in hypertensive patients. On the other hand, increased serum concentration of the carboxy-terminal procollagen type I-derived peptide was found in spontaneously hypertensive rats compared with normotensive Wistar-Kyoto control rats. An association was found between the serum concentration of this peptide and the extent of myocardial fibrosis and the hydroxyproline concentration in the left ventricle of spontaneously hypertensive rats. It is proposed that procollagen-derived peptides in serum may be markers of exaggerated collagen tissue synthesis involved in hypertensive myocardial fibrosis.

Animals↗
PubMed1995

Increased serum concentrations of procollagen peptides in essential hypertension. Relation to cardiac alterations.

BACKGROUND: The serum concentrations of two procollagen-derived peptides, procollagen type III amino terminal peptide (PIIIP) and procollagen type I carboxy terminal peptide (PIP), have been proposed as useful markers of the tissue synthesis of collagen type III and type I, respectively. Therefore, this study was designed to evaluate fibrogenic activity in patients with essential hypertension by measuring serum PIIIP and PIP. Furthermore, since hypertensive heart disease is characterized by myocardial accumulation of collagen type III and type I, a second aim of the study was to assess whether some relation exists between the serum concentrations of PIIIP and PIP and several parameters of left ventricular anatomy and function in hypertensive patients. METHODS AND RESULTS: The study was performed in 50 patients with never-treated essential hypertension and in 30 normotensive control subjects. Measurements were repeated in 43 hypertensive patients after 6 months of treatment with the angiotensin-converting enzyme inhibitor lisinopril. The serum concentrations of PIIIP and PIP were measured by specific radioimmunoassay. Two-dimensional, targeted M-mode and Doppler ultrasound recordings were obtained in every subject to determine several parameters of the left ventricle anatomy and function. Ambulatory ECG monitoring was performed in each patient, and the recorded ventricular arrhythmias were categorized according to Lown-Wolf classification. Baseline serum PIIIP and PIP were increased (P < .001) in hypertensive patients as compared with normotensive subjects. An inverse correlation was found between serum PIIIP and the ratio between maximal early transmitral flow velocity and maximal late transmitral flow velocity measured during diastole (r = .3786, P < .01) in the group of hypertensive patients. Serum PIP was correlated directly with the left ventricular mass index (r = .3277, P < .05) in the group of hypertensive patients. Serum PIP concentrations increased in parallel with the increase in the grade of ventricular arrhythmias in the group of hypertensive patients. Treated patients attained normalization in blood pressure, amelioration of diastolic filling, regression of left ventricular mass index, and a diminution in the number of daily ventricular extrasystoles. In addition, serum PIIIP and PIP concentrations decreased significantly (P < .001) to normal values in patients treated with lisinopril. CONCLUSIONS: These findings suggest that tissue synthesis of collagen type III and type I is abnormally increased in essential hypertension and can be normalized by treatment with lisinopril. On the other hand, our results suggest that serum PIIIP and PIP are related to several anatomic and functional alterations of the hypertensive left ventricle. Serum procollagen peptide measurements may therefore provide indirect diagnostic information on the myocardial fibrosis associated with arterial hypertension.

Collagen↗
PubMed1995

Insulin-like growth factor binding proteins in arterial hypertension: relationship to left ventricular hypertrophy.

OBJECTIVE: It was reported previously that circulating insulin-like growth factor I levels are abnormally elevated in patients with essential hypertension and left ventricular hypertrophy. Tissue availability of the factor depends on the distribution of the circulating bound factor between its high- and low-molecular mass binding proteins, only the latter being able to cross the endothelium. The aim of this study was to investigate whether the presence of the different serum binding proteins is altered in patients with essential hypertension and left ventricular hypertrophy. DESIGN: The study was performed in 30 never-treated patients with essential hypertension and 30 age- and sex-matched normotensive subjects. Patients were separated into two groups according to the presence or the absence of echocardiographically determined left ventricular hypertrophy. METHODS: Plasma insulin-like growth factor I levels were determined by specific radioimmunoassay. The different molecular forms of its serum binding proteins were analysed by Western blotting using [125I]-labelled insulin-like growth factor I. A densitometric scanning of the blots was performed to analyse the quantitative relationships between the different forms of binding proteins. RESULTS: Insulin-like growth factor I levels were significantly higher in the hypertensive patients with than in the hypertensive patients without left ventricular hypertrophy or in the normotensive subjects. Compared with the normotensive subjects, both hypertensive patients subgroups exhibited increased high-molecular mass binding protein type 3 and decreased low-molecular mass binding proteins types 1 and 2. However, changes in the binding proteins were more marked in the hypertensive patients without than in the hypertensive patients with left ventricular hypertrophy. Accordingly, the ratio of low- to high-molecular mass binding proteins (an index of insulin-like growth factor I bioavailability) was higher in the hypertensive patients with than in the hypertensive patients without left ventricular hypertrophy. CONCLUSIONS: These results show that the distribution of the molecular forms of serum insulin-like growth factor binding proteins is altered in patients with essential hypertension, independently of insulin-like growth factor I levels. This suggests that regulation of the binding proteins is abnormal in essential hypertension. Whether the tissue availability of circulating insulin-like growth factor I is higher in hypertensive patients with than in hypertensive patients without left ventricular hypertrophy merits further investigation.

Adult↗
PubMed1994

Peroxisome enzyme modification and oxidative stress in rat by hypolipidemic and antiinflammatory drugs.

Changes in the activities of two peroxisomal enzymes (catalase and thiolase), some parameters related to oxidative situations, such as conjugated dienes, zinc, iron, copper and superoxide dismutase after the administration of two known peroxisome proliferators (clofibrate and acetylsalicylic acid), and two drugs pharmacologically related to the former (probucol and diflunisal) have been studied in male Wistar rats. Administration of the drugs was made by p.o. for 15 days. After the treatment the rats were killed, their livers and brains were taken out, and their blood was collected. Peroxisomes were purified by differential centrifugation followed by ultracentrifugation. Total RNA was also extracted and the acyl CoA oxidase mRNA expression was studied. Clofibrate was inactive on both enzymes studied in liver and diflunisal in brain. However, the acyl CoA oxidase mRNA expression increased by clofibrate treatment. Results are justified by the liposolubility and protein-binding properties of the drugs. Otherwise, the present results show the existence of an increased lipid peroxidation, lower value of superoxide dismutase, and variable results for zinc, copper and iron trace elements. These data evidence an oxidative stress situation in plasma of rats treated with these drugs, probably as a consequence of an increase in some beta-oxidation enzymes, which brings about an overproduction of H2O2.

Acetyl-CoA C-Acetyltransferase↗
PubMed1992

Extracellular fluid expansion during parenteral refeeding.

Life emerged on our planet from a fluid environment which probably contained a similar concentration of sodium and other electrolytes to that of the extracellular fluid of mammals (1). The maintenance of the volume and composition (homeostasis) of this internal fluid surrounding all the body cells is essential for survival. Malnutrition and illness are associated with alterations in the distribution and in the renal handling of water and sodium within the body (2). Thus, an understanding of water and salt physiology is essential for the proper practice of nutritional support.

Journal Article↗
PubMed1992

The influence of calorie source on water and sodium balances during intravenous refeeding of malnourished rabbits.

34 New Zealand rabbits were starved until a mean weight loss of 15% to 20% was achieved and then were parenterally re-fed with four different total parenteral nutrition (TPN) formulae for 6 days. Regimens were isocaloric (85 kcal/kg/day) and isonitrogenous (0.52 gN/kg/day) with the following formulae: group S-GLU-70 (water 100 ml/kg/day, Na 7 mEq/day and 70 30 % of calories as glucose/lipids, n = 9), group S-GLU-50 (water 100 ml/kg/day, Na 7 mEq/day and 50 50 % of calories as glucose/lipids, n = 9), group L-GLU-30 (water 70 ml/kg/day, no sodium and 30 70 % of calories as glucose/lipids, n = 8) and group L-GLU-50 (water 70 ml/kg/day, no sodium and 50 50 % of calories as glucose/lipids, n = 8). The group S-GLU-70 showed the highest water and sodium balances (p = 0.001 respectively, ANOVA test). Group S-GLU-70 showed also a greater weight gain (p = 0.0001) and, although not statistically significant, the lowest albumin at the end of the TPN. Glucose load appears to be responsible for the rapid weight gain and positive water and sodium balances during TPN in depleted non-stressed animals.

Journal Article↗
PubMed1992

Conformational changes of S-1 related to its dissociation from actin.

The peptide pattern obtained after proteolysis of S-1 with trypsin was different in the absence or presence of anions. The affinity of tryptic and undigested S-1 for anions (CN-, SCN- or HCO3-) was different, as reflected by the altered values of Ki or Ka obtained from ATPase activity measurements. Anions CN-, SCN-, HCO3-, or PPi induced dissociation of actomyosin when added to acto-S-1 or acto-heavy-meromyosin. Among nucleoside di- and triphosphates, only triphosphates were effective with regard to the dissociation. The results suggest the existence of a regulatory site of cationic nature on S-1, which might be involved in the dissociation of actin from myosin.

Actins↗
PubMed1991

Water and sodium metabolism during intravenous re-feeding in the malnourished rabbit.

Twenty-three New Zealand rabbits were starved until a mean weight loss of 21% was achieved and then re-fed parenterally with two different total parenteral nutrition (TPN) formulae: a standard formula (Group SF, n = 12) containing 100 ml/kg/day of water, 7 mEq/day of sodium and 70% of non-protein calories as glucose; and a modified formula (Group MF, n = 11) containing 70 ml/kg/day of water, no sodium and 70% of non-protein calories as fat. After 6 days of parenteral nutrition, Group SF showed a higher weight gain than Group MF (10 +/- 5.8% vs. 1.4 +/- 5%; p = 0.001) and serum albumin concentration in Group SF was lower than in Group MF (25.9 +/- 4.2 vs. 32 +/- 4.5 g/l; p = 0.004). There was a close correlation between weight gain and water and sodium balances (r(2) = 0.714; p = 0.0001 and r(2) = 0.447; p = 0.0005, respectively). In Group SF, a close correlation was found between the free water clearance and water balance (r(2) = 0.711, p = 0.0006). In conclusion, in Group MF water and sodium restriction led to a better nutritional response in terms of improving serum albumin concentrations and minimising weight gain, probably due to less expansion of the extracellular fluid compartment in this group.

Editorial↗
PubMed1989

Treatment of 27 postoperative enterocutaneous fistulas with the long half-life somatostatin analogue SMS 201-995.

Twenty-seven patients with postoperative enterocutaneous fistulas were treated with parenteral nutrition and SMS 201-995 (100 micrograms/8 hours, subcutaneously), a long half-life somatostatin analogue. At the time SMS 201-995 was started, 11 patients had low output fistulas (less than 1000 ml/48 hours), 11 patients had high output fistulas (above 1000 ml/48 hours), and 5 patients had fistulas sitting in large abdominal wall defects. Within 24 hours of treatment, a mean reduction of 55% of the fistula output was observed. Fistula site or output before treatment had no influence on the magnitude of output reduction. Spontaneous closure was achieved in 77% of the patients after a mean of 5.8 +/- 2.7 days of treatment with this drug. Two patients died (7.4%). Pain at the injection site was referred by 15% of the patients but no other side effects were observed. Glucose intolerance was not observed. SMS 201-995 has been shown to be very useful in the conservative treatment of enterocutaneous fistulas because of its ability to rapidly reduce fistula output and accelerate spontaneous closure.

Adult↗
PubMed1987

Blind evaluation of the effect of octreotide (SMS 201-995), a somatostatin analogue, on small-bowel fistula output.

In a blind crossover trial for 4 days, after at least 7 days on conventional treatment, 14 patients with postoperative small-bowel fistula were randomised to 2 days on a somatostatin analogue, octreotide (SMS 201-995), followed by 2 days on placebo (group 1) or vice versa (group 2), after which all patients were treated with octreotide until the fistula closed or reoperation was deemed necessary. In group 2 mean fistula output was reduced from 698 ml per 24 h pretreatment to 246 mg per 24 h after 2 days on octreotide; output increased from 228 ml per 24 h to 497 ml per 24 h when treatment with octreotide was interrupted by placebo. In 11 patients fistulae closed spontaneously in an average of 4.5 days after continous treatment with octreotide.

Adult↗
PubMedDate not supplied

[Studying of gastric emptying for solids and liquids by means of using stable isotopes].

The study of gastric emptying is usually performed by scintigraphy. Over the last years alternative non radioactive methods have been developed based on the stable isotopes technology. Such techniques use 13C-octanoic acid to measure gastric emptying of solids and sodium 13C-acetate to measure liquids emptying. The enrichment of 13C in breath air along the time reflects the velocity of gastric emptying. Kinetic parameters can be obtained from this enrichment to quantify gastric emptying. Samples can be obtained outside the processing laboratory. Due to the characteristics of the method, it is adequate and safe to evaluate pathologies related to gastric emptying and the efficiency of the therapy.

Acetates↗